This quest will unlock after completing the "...And My Sugar?" quest. To start it, you must head to the Governor's mansion and speak with the guards guarding the entrance gate.
Disguised as the Assassin Duncan Walpole, Edward must deliver various maps and a strange crystal cube to the Governor of Havana.
Once the guards open the gate for you, head into the estate grounds and follow the avenue toward the marker. Two gentlemen - Woodes Rogers and Julien du Casse - will greet you at the location. After exchanging pleasantries, they'll invite you to take part in a shooting challenge, which actually serves as an introduction to another mechanic available in the game - pistol shooting.
You must shoot five dummies with your pistol. Once you do that, you will have to do it again - but this time, you will have 30 seconds. This is plenty of time, so you shouldn't have the slightest problem completing the task, even factoring in the need to reload your pistol.
After completing the task, you will receive new hidden blades from one of your companions.
Follow your companions to the next spot, where they've set up another training course and will ask you to demonstrate your assassin skills.
To complete this challenge, perform the following actions:
Hide in the hay cart and perform an assassination on the dummy standing next to the cart.
Hide behind the wall of the house and perform a corner assassination on the dummy.
Perform a sprinting assassination on the dummy standing in the open field.
Climb onto the roof and perform an air assassination on the dummy standing next to the building.
Follow your hosts once again, who will lead you to Governor Torres this time. Once you arrive, another cutscene will play - you and your companions will be sworn into the Templars and receive appropriate rings - Templar Ring. Next, a meeting will begin. You can calmly wait for it to end or optionally pickpocket those gathered around the table or review the documents left on the table in the meantime.
After the meeting ends, you will receive another quest item - Curious Schematic - and then leave the governor's estate.
After the meeting, head to the tavern and speak with the innkeeper. He will refuse to give you a room due to the earlier brawl.
Hint:
Climb onto the roof of the tavern and lie down on the bench at the table to finish this quest. You will thereby unlock the next main quest - A Man They Call the Sage.
